The aorta is the main blood vessel that comes out of the heart and distributes blood to the whole body. In some people, the aorta becomes swollen (aneurysm) and bursts, especially as it passes through the abdomen. These 'abdominal aortic aneurysms' often occur without symptoms and can burst or rupture without warning. This usually leads to death and represents the thirteenth commonest cause of death in the United Kingdom. In this study, we are looking at a new technique that can look at the aortic aneurysm using magnetic resonance imaging; a technique that does not require x-rays or radiation. We have recently shown that, using magnetic resonance combined with a new imaging agent USPIO, we can detect 'hotspots' of activity in these aneurysms that seem to predict which aneurysms grow rapidly, and are therefore potentially at risk of rupture. We here propose to conduct a study in Edinburgh that will invite all patients who are under surveillance because of an aneurysm. We will image these patients using this novel technique and see if we can identify which patients burst their aneurysm, have an aneurysm that grows so large it needs to have surgery, or die. This will be important to establish as it will potentially lead to a new way of managing people that could ultimately save lives. This is particularly timely as national screening and surveillance programmes are currently being launched.